Home Security: Security Lighting Considerations

An important element of your home security “system” is proper security lighting. Criminals wish to remain unobserved and good outdoor lighting can discourage many of them from considering your home as a target. Of the many security lighting options that are available, which one is the “best”?

The first thing to look at is efficiency. Efficiency is a measure of the amount of light emitted (lumens) for a given amount of energy consumed (watts). The light source that produces the most lumens per watt is the most efficient. Another consideration is lamp life. Cheap bulbs that need frequent replacement may actually be more expensive than costlier bulbs that lasts much longer. The third characteristic is color rendition. This tells you how natural an illuminated person or object will look. A fourth thing to consider is how fast it reaches full intensity. Some types of lighting have a delay when they start up.

There are basically three types of lighting that can be used for home security: 1) incandescent lighting; 2) fluorescent lighting; and 3) high intensity discharge lighting. Each one has advantages and disadvantages. Let’s take a look at each type and compare them.

Incandescent Lighting

This is the ubiquitous light bulb that is found in nearly every room of your house. Most people use this to light their front and rear doors. Incandescent lighting is the most inefficient of all three types. It emits light by heating a small filament to a white hot glow. About 90% of the energy it consumes is used to create the heat, while only 10% is actually converted to light. Illuminated objects have a natural appearance under incandescent lighting. The bulbs are inexpensive, but they also have the shortest life. They are best suited as security lighting in applications where they will be turned on only briefly or full illumination is required immediately, even in very cold weather.

Lumens per Watt = 15 to 25
Average Life = 750 to 2,000 hours

Fluorescent Lighting

This lighting can be in the form of tubes, or compact fluorescent lights (CFL) that have built-in ballasts and can be screwed into regular incandescent light sockets. Fluorescent lighting is about four times more efficient than incandescent lighting and lasts nearly 25 times as long. In the past, frequently turning fluorescent bulbs on and off shortened their life-span, but this is not true with modern fixtures. These lights also illuminate with a natural color. All of this would seem to make fluorescent lighting a hands-down winner over incandescent bulbs. But CFLs require a short warm-up period to reach full brightness. In cold weather, this warm-up period is considerably longer, and in very cold weather, they may not turn on at all.

Lumens per Watt = 33 to 70
Average Life = 10,000 to 20,000 hours

High Intensity Discharge Lighting

This is often called HID lighting. HID lighting is the most efficient, and has the longest bulb life of the three lighting types. But, it has a delay when first starting up before it reaches full brightness. The time it takes the light to restart after being turned off, also called “re-strike” time, is even longer (3 to 5 minutes). This makes HID lighting unusable for security lighting applications that require an instant start. They are best suited for area lights that will be on for long periods of time (at least an hour). There are four types of HID lighting: 1) low-pressure sodium (LPS); 2) high-pressure sodium (HPS); 3) mercury-vapor (MV); and 4) metal-halide (MH).

LPS is the most efficient lighting source of all, but it is rarely used in the United States. The red-orange light does not look at all natural and the actual color of illuminated objects is severely distorted. Also, the fixtures themselves are larger than those of the other HID light sources.

Lumens per Watt = 80 to 180
Average Life = about 20,000 hours

HPS produces the orange-gold color you see in many parking lots. It is second only to LPS lighting in efficiency and has a high life expectancy similar to MV lighting.

Lumens per Watt = 45 to 110
Average Life = about 24,000

MV lighting has the longest lamp life. It also produces a more natural color than LPS or HPS. Although its efficiency is higher that incandescent lighting, it is significantly lower than the other types.

Lumens per Watt = 13 to 48
Average Life = over 24,000 hours

MH lighting produces the most natural light of all the HID lighting sources. Its efficiency and lamp life are a little lower than HPS lighting.

Lumens per Watt = 60 to 110
Average Life = about 20,000 hours

The “best” type of lighting is the one that best fits your particular security lighting application. Only you can you can determine if energy cost (efficiency), replacement cost over time (average lamp life), the color of the light, or how fast it turns on is most important. At least now you can make those comparisons.